Neurological soft signs in bipolar I disorder patients

Abstract

Background: Neurological soft signs (NSS) have been reported to be more prevalent in patients with schizophrenia compared to other psychiatric and non-psychiatric controls. However, this issue in bipolar I disorder seems to be understudied.

Aims: The aims of the study were to examine the extent to which NSS are associated with bipolar I disorder cases compared to healthy controls, to assess the possible relationship between NSS and clinical dimensions of the disorder, and to explore the association of sociodemographic characteristics with the occurrence of NSS in cases with this disorder.

Methods: Predominantly treatment naïve cases of bipolar I disorder from rural communities were assessed for NSS using the Neurological Evaluation Scale (NES).

Results: This study showed that patients with bipolar I disorder performed significantly worse on two NES items from the sensory integration subscale, on one item from motor coordination and on four items from the 'others' subscale, the highest difference in performance being in items under the sequencing of complex motor acts subscale. Clinical dimensions and sociodemographic characteristics appeared to have no relationship with NES total score.

Conclusions: Bipolar I disorder patients seem to have more neurological dysfunction compared to healthy controls particularly in the area of sequencing of complex motor acts. In addition, the finding suggests that NSS in bipolar I disorder are stable neurological abnormalities established at its onset or may be essential characteristic features of the disorder representing stable disease process that existed long before its onset.